Coatings derived from copolymers of polymerizable azlactones and olefinically unsaturated monomers are known. Such coatings are derived, in general, from rigid, high glass transition temperature (Tg), hydrophobic copolymers. Crosslinking is accomplished by dispersing or dissolving the azlactone copolymer with a crosslinking agent, generally in an approximately stoichiometric amount to the azlactone, in a volatile organic liquid, applying the mixture to a substrate, then allowing the coating to crosslink via azlactone ring-opening reactions with the crosslinking agent. Suitable crosslinkers are polyols and polyamines. Polyamines, such as ethylene diamine, react with azlactones at room temperature, thereby forming crosslinks. Because of the rapid reaction between azlactones and primary amines, incorporation of a ketone solvent in the coating mixture is desirable. Polyols react much slower with azlactones and generally require a catalyst, such as a strongly acidic or basic catalyst, to promote crosslinking.
Various coatings derived from azlactone copolymers are known. For example, known coatings include copolymers of 2-alkenylazlactones with acrylic acid esters and copolymerizable vinylidene compounds having at least one hydroxyl group that crosslink on drying or mild heating. Such polymers crosslink by reaction of the hydroxyl groups on one chain of the polymer with azlactone groups on other chains. In general, an acidic or basic catalyst is again needed to facilitate the crosslinking reaction. Coatings derived from azlactone copolymers that are crosslinkable by exposure to radiation are useful in imaging applications. Uncrosslinked azlactone copolymers may be used to coat a variety of substrates. These coated substrates can be used for the immobilization of functional materials, including biologically active species such as proteins. Crosslinked azlactone-functional moieties may be included in a coating over the surfaces of chemically reactive, porous supports. These reactive supports can, in turn, be reacted with biologically active materials to produce adduct supports.
While there are a variety of methods for producing coatings derived from azlactone-functional materials, some of which provide azlactone-functional coatings useful for the immobilization of other species, there remains a need for additional or improved methods for providing coated materials for use in the immobilization of biologically active materials.